_____________________________________________________________________________________________________
Deciphering Pearl Millet Grain Yield under Water Stress using Genotypic, Phenotypic Correlation and Path Coefficient Analysis
Amit Kumar
a*, Mukesh Kumar Yadav
a, Heeralal Barupal
a, Mukut Bihari Meena
b, Ravi Kumawat
aand Kinjal Mondal
ca Department of Genetics and Plant Breeding, Maharana Pratap University of Agriculture and Technology, Udaipur, 313001, Rajasthan, India.
b Department of seed Science and Technology, Hemvati Nandan Bahuguna Garhwal University Uttarakhand, India.
c Department of Molecular Biology and Biotechnology, Maharana Pratap University of Agriculture and Technology, Udaipur, 313001, Rajasthan, India.
Authors’ contributions
This work was carried out in collaboration among all authors. All authors read and approved the final manuscript.
Article Information DOI: 10.9734/IJECC/2022/v12i1030796
Open Peer Review History:
This journal follows the Advanced Open Peer Review policy. Identity of the Reviewers, Editor(s) and additional Reviewers, peer review comments, different versions of the manuscript, comments of the editors, etc are available here:
https://www.sdiarticle5.com/review-history/86336
Received 22 February 2022 Accepted 30 April 2022 Published 07 May 2022
ABSTRACT
Yield is a polygenic character, usually depends on its various contributing traits like days to 50%
flowering, plant height, and panicle length as well as panicle girth. A study was conducted during kharif 2018 to evaluate the relationship between grain yield and its components in pearl millet using correlation and path analysis studies. In the current study, significant genotypic and phenotypic correlations were found among five yield contributing traits in eighteen pearl millet hybrids. The traits including days to 50% flowering, plant height, and panicle length were found to have positive correlation with grain yield per plantthat implied the importance of those traits in selection of high yielding hybrids. Grain yield per plant was used as a dependent character in path-coefficient analysis at the genotypic level. Plant height and panicle length were the independent variables (cm). The highest positive and direct effect was found for days to 50 percent flowering (0.9946) followed by panicle diameter (cm) (0.5726). Pearl millet having deep root system are often found to survive even in various stressful conditions including water stress. These characteristics have made
Original Research Article
it popular in dry and semi-arid regions around the world; nevertheless, compared to other major cereals, less work has been put into the study of climate-resilient characteristics of pearl millet. We have revealed here some basic ideas of correlation between the grain yield of pearl millet with its yield contributing constituents under drought condition.
Keywords: Correlation; yield; pearl millet; path coefficient; drought.
1. INTRODUCTION
Pearl millet [Pennisetum glaucum (L.) R. Br.], or commonly known as bajra (2n = 14) belonging to the family Poaceae (earlier Gramineae) is a heterogenous as well as heterozygous highly cross-pollinated crop and protogynous in nature [1]. In India, pearl millet ranks fourth amongst the most widely cultivated food crop after rice, wheat, and maize. Total cultivable area covers 6.93 million ha throughout the nation and secures 8.61 million tons of annual production with productivity 1,243 kgha−1 [2]. Pearl millet is thought to be originated in West Africa [3].
Nigeria, Pakistan, Sudan, and Saudi Arabia
contribute as the major pearl millet growing countries throughout the globe. In India,
the major pearl millet growing states are
Rajasthan, Maharashtra, Gujarat, Uttar Pradesh and Haryana, covering nearly 90% acre
[4].
Nutritionally, the energy value, protein and macro nutrient contents of millets is comparable
and sometimes higher than conventional cereals. In the context of nutritional status, pearl
millet is reported to contain 92.5% dry matter, 2.1% ash, 2.8% crude fiber, 7.8%
crude fat, 13.6% crude protein, and 63.2% starch [5].
Drought is one of the most impeding abiotic stress factors retarding plant growth and development [6]. Drought is a serious issue to pearl millet during its flowering and grain filling stages [7,8]. Usually, development of drought- tolerant hybrids is hindered by poor understanding of the mechanisms of drought tolerance as well as inadequate selection techniques [9,10]. Low heritability of drought tolerance also contributes in hampering development of drought-resilient hybrids since an era. Strategies for improving drought tolerance include selection of hybrids in low stress environments, high stress environments, a combination of stress and no stress environments [11].
Correlation studies are used to determine the nature and extent of relationships between yield and other yield attributing traits in order to better understand the traits that influence yield. A plant breeder's primary goal is to improve yield and stability. As a result, correlation analysis of a particular trait with other yield-related traits is critical for selecting lines with higher yield. The correlation coefficient can be partitioned into direct and indirect effects using path coefficient analysis. The goal of this study was to determine the genotypic and phenotypic correlations, as well as the direct and indirect contributions of various traits to yield.
2. MATERIALS AND METHODS
For the current study, eighteen hybrids of pearl millet were collected from the Rajasthan Agriculture Research Institute, Durgapura, Jaipur under the supervision of Sri. Karan. Narender.
Agriculture. University, Jobner. Those hybrids were planted in a three-replication randomized block design. Each hybrid was planted in a two- row experimental plot measuring 1 meter in length, with 45 x 10 cm inter and intra row spacing. The hybrids were tested in three replications under both the water-rich and water- stressed conditions. Days to 50% flowering, plant height (cm), panicle length (cm), panicle diameter (cm), and grain yield per plant were recorded. In each replication, observations were made on five randomly selected plants from each plot.
2.1 Statistical Analysis
To better understand, the associations and relationships between traits, the genotypic and phenotypic correlation coefficients were calculated using the method described by Singh and Chaudhary [12]. Path analysis was used to divide the genotypic and phenotypic correlation coefficient into direct and indirect effects in order to establish a cause-and-effect relationship between the traits, as suggested by Dewey and Lu [13].
Table 1. List of hybrids used in the study
S. No. Hybrids S. No. Hybrids
1 RHB-173 10 HHB-67
2 RHB-177 11 HHB-197
3 RHB-223 12 HHB-299
4 RHB-233 13 9450
5 RHB-234 14 9001
6 GHB-538 15 86-M-86
7 GHB-558 16 MCPH-17
8 GHB-744 17 MARU-TEJ
9 GHB-905 18 KBH-108
Table 2. Characters to be recorded
S.NO Characters to be recorded
1 Days to 50% flowering
2 Plant height
3 Panical lenth
4 Panical girth
5 Grain yield
3. RESULTS AND DISCUSSIONS 3.1 Correlation Coefficient
Grain yield is a complex trait, influenced by a number of factors. As a result, character association was investigated in the current study to assess the relationships between yield and its components in order to improve the usefulness of selection. In general, genotypic correlations are shown to be higher than phenotypic correlations, indicating that though there is strong influence of environment and considering the importance of phenotypic correlation. Correlation coefficient analysis determines the component characters on which selection can be used for genetic yield improvement by measuring the natural relationship between various plant traits.
Table 3 and 4 shows the phenotypic and genotypic correlation coefficients between the traits under investigation. The results revealed that traits, namely, panicle length and panicle diameter exhibited significant positive phenotypic and genotypic correlation with grain yield. Grain yield had Positive and non-significant genotypic correlation was recorded with days to 50 per cent flowering (0.2987NS), while positive and significant correlation was observed with panicle length (0.0407*) and panicle diameter (0.455*) (Table 3). Grain yield per plant exhibited significant positive association with panicle diameter followed by panicle length and plant height. These findings are similar to those of earlier studies in pearl millet on various traits,
such as grain yield, panicle length [14], panical diameter [15], and plant height. (Shashikant et al., 2012). Grain yield per plant exhibited non- significant association with days to 50% flowering and plant height. The similar findings are reported in pearl millet on various traits, such as grain yield, days to 50% flowering [15], and plant height. (Shashikant et al., 2012).
Positive and non-significant phenotypic correlation with plant height (0.0551), while positive and significant correlation was observed with panical length (0.2339*) and panicle diameter (0.535*) (Table 4).
It had negative and significant phenotypic correlation with days to 50 per cent flowering (- 0.394**). Similar observations were also reported for days to panicle diameter [16], Bello et al., [17]
and Khairwal et al., [18]. Grain yield had negative and non- significant genotypic correlation with plant height (-0.097NS).
The positive correlation of grain yield with these characters implies that improving one or more of these traits could result in higher grain yield for pearl millet.
3.2 Path Coefficient
By partitioning the correlation, the path coefficient analysis allows separation of the direct and its indirect effects through other variables [19].
The characters with the strongest direct effect on grain yield were days to 50 percent flowering (0.9946) followed by panicle diameter (0.5726) according to the path coefficient analysis at the genotypic level.
The strong relationship between grain yield per plant and the days to 50 percent flowering, panicle length and panicle diameter proved to be
the key determinant [20]. Plant height (-0.3339) and panicle diameter (-0.2735) had negative direct effect on grain yield. Similar findings reported by Patil and Jadeja (2005). For genotypic path coefficient analysis, the residual effect was 0.5980. The residual effect is moderate, it indicates that the characters studied, there are some other attributes which contribute for grain yield.
Table 3. Genotypic correlation coefficients for five traits in hybrids of pearl millet
Traits DF PH PL PD GY
DF 1 0.762** -0.0348 -0.6031** 0.2987NS
PH 1 0.2707 0.6575** -0.097NS
PL 1 0.446* 0.0407*
PD 1 0.455*
GY 1
*, ** Significant at 5 and 1 per cent level. DF = days to 50% flowering, PH = plant height, PL = panicle length, PD
= panicle diameter, GY = grain yield plant -1
Table 4. Phenotypic Correlation coefficients for five traits in hybrids of pearl millet
Traits DF PH PL PD GY
DF 1 0.521** 0.1573 0.0422 -0.394**
PH 1 0.1875 0.278* 0.0551NS
PL 1 -0.041 0.2339*
PD 1 0.535*
GY 1
*, ** Significant at 5 and 1 per cent level. DF = days to 50% flowering, PH = plant height, PL = panicle length, PD = panicle diameter, GY = grain yield plant -1
Fig. 1. Correlalogram of yield contributing traits studied under the current investigation
-1 -0.8 -0.6 -0.4 -0.2 0 0.2 0.4 0.6 0.8
GY PL DF PH 1
PD
GY
PL
DF
Table 5. Direct and indirect effects (genotypic level) of yield contributing traits on grain yield plant-1 (g) in hybrids of pearl millet
Traits DF PH PL PD
DF 0.9946 0.7579 0.35 -0.5998
PH -0.2545 -0.3339 -0.1194 0.0324
PL -0.0962 -0.0978 -0.2734 -0.0399
PD -0.3453 -0.0556 0.0836 0.5726
GY 0.2987 0.2707 0.0407 -0.0348
Partial R2 0.2971 -0.0904 -0.0111 -0.0199
Fig. 2. Genotypic path diagram for grain yieldplant-1
4. CONCLUSION
Eighteen hybrids of pearl millet were evaluated in randomized block design to determine yield and yield component relationships. The results revealed that panical length and panical diameter expressed positive and significant correlation with grain yield. Grain yield per plant exhibited significant positive association with panicle diameter followed by panicle length and plant height. Grain yield per plant exhibited non- significant association with days to 50% flowering and plant height.
key yield contributing traits in pearl millet are panical diameter and panicle length, according to correlations and path studies.
COMPETING INTERESTS
Authors have declared that no competing interests exist.
REFERENCES
1. Animasaun DA, Morakinyo JA, Mustapha OT, Krishnamurthy R. Genome size and ploidy variations in pearl millet (Pennisetum glaucum) and napier grass (Pennisetum purpureum) genotypes. Acta Agronómica. 2019;68(4):299-305.
2. Directorate of Millets
Development. Department of Agriculture, Co-operation and Farmers Welfare, Ministry of Agriculture and Farmers Welfare, Government of India; 2020.
3. Vavilov SI. Microstructure of light. Russian edition of USSR academy of science, Moscow; 1950.
4. Anonymous. ajasthan Agricultural Statistics at a Glance. Commission rate of Agriculture, Rajasthan, Jaipur (Statistical cell); 2000.
5. Ali MA, Tinay AH, Abdalla AH. Effect of fermentation on the in vitro protein
digestibility of pearl millet. Food Chemistry. 2003;80(1):51-54.
6. Bruce WB, Edmeades GO, Baker TC.
Molecular and physiological approach to maize improvement for drought tolerance.
Journal of Experimental Botany.
2002;53:13-25.
7. Garrity PD, Sullivan CY, Watts DG.
Moisture deficits and grain sorghum performances: Drought stress conditioning.
Agron. J. 1983;75: 997 – 1004.
8. Hattendorf MJ, Dedelfs B, Amoss LR, Stone RE. Comparative water uses characteristics of six row crops. Agron. J.
1988;80:80 – 85.
9. Bruckner PL, Frohberg RC.. Stress tolerance and adaptation in spring wheat.
Crop Sci. 1987;27:31- 36.
10. Richards RA. Defining selection criteria to improve yield under drought. Plant Growth Regulation. 1996;20:157 – 166.
11. Byrne DF, Bolonas J, Edameales GO, Eaton DL. Gain from selection under drought versus multi location testing in related tropical maize populations. Crop Sci. 1995;35: 63 – 69.
12. Singh RK, Chaudhary BD. Biometrical methods in quantitative genetic analysis. Biometrical Methods in Quantitative Genetic Analysis; 1977.
13. Dewey DR, Lu KH. A correlation and path coefficient analysis of crested wheat grass seed production. Agron. J. 1959;51:515- 518.
14. Singh OV, Singh AK. Analysis of genetic variability and correlation among traits in exotic germplasm of pearl millet [Pennisetum glaucum (L.) R. Br.]. Indian
Journal Agricultural Research.
2016;50(1):76-79.
15. Izge AU, Alai SO, Maina YT. Correlation and path analysis of pod yield and yield components of groundnut (Arachis hypogeae L.). J. Sustain. Agric. Environ.
2006;6(1):15-21.
16. Abubakar A, Falusi OA, Olayemi IK, Adebola MO, Daudu O, Dangana MC. ().
Evaluation of pearl millet (Pennisetum glaucum L. (R. Br.)) landraces for resistance to stem borer (Coniesta ignefusalis Hampson.) Infestation; 2020.
17. Bello D, Kadams AM Simon SY.
Correlation and path coefficient analysis of grain yield and its components in sorghum (Sorghum bicolor L. Moench). Nig. J. Trop.
Agric. 2001;3:4-9.
18. Khairwal IS, Rai KN, Andrew DJ, Harinarayana G. Pearl millet breeding.
Oxford and IBH Publishing Co. New Delhi.
1999:511.
19. Wright S. Correlation and causation.
Journal of Agricultural Research.
1921;20:557-585.
20. Rakesh G, Dayakar Reddy T, Shashibhushan D, Bhave MHV. Character association and path coefficient analysis for grain yield and its components in pearl millet [Pennisetum glaucum (L.) R.Br.].
Ecology, Environment and Conservation.
2015;21(3):1325-1330.
21. Patil HE, Jadeja GC. Correlation and path analysis under terminal water stress condition in pearl millet [Pennisetum glaucum (L.) R. Br.]. Indian Journal of Dryland Agricultural Research and Development. 2005;20 (1):31-34.
© 2022 Kumar et al.; This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Peer-review history:
The peer review history for this paper can be accessed here:
https://www.sdiarticle5.com/review-history/86336
